Fluid pumping and separation apparatus

Abstract

Pumping apparatus is provided for separating liquids from solids in a mixture thereof, the apparatus preferably being of the peristaltic type with a cage with rollers circumferentially spaced around its periphery rotable within a casing, there being at least two flexible tubes extending around the cage, a first, evacuation tube having an inlet end held open within the casing and an opposite end connected to a first outlet in the casing and a second pumping tube extending between an inlet in the casing adapted to be connected to a liquid to be pumped and a second outlet from the casing, whereby upon rotation of the cage, e.g. by an electric motor, a negative pressure will be generated within the casing and the liquid will be pumped through the apparatus. For separating solids suspended in/mixed with the mixture being pumped, an electrical or electrostatic charge is introduced into the mixture. To prevent the tubes from wandering laterally and becoming worn within the casing, a plurality of guide spools is located on the cage, preferably circumferentially alternating with the rollers on the cage. The electrical or electrostatic charge within the mixture may be generated using electrodes and a low voltage AC current, or with polypropylene brushes, or strands or polypropylene located in a pumping tube.

1 . A pumping apparatus for separating solids fromom liquids in a fluid mixture of solids and liquid, comprising a pump for pumping the fluid mixture from a supply thereof through a pipe into a settling tank, means to introduce an electrical charge into the fluid mixture whereby solids will precipitate from the fluid mixture in the settling tank.  
     
     
         2 . A peristaltic pumping apparatus comprising at least two fexible deformable tubes entrained around a cage, rotatable within a part arcuate casing and supporrng a plurality of rollers with push fluid through the tubes by squeezmg the tubes, a first one of the tubes having a first end held open to the intenor of the casing and an opposite end connected to a first outlet from the casing, whereby, upon operation of the apparatus, a pressure (hereinafter called negative pressure) which is less than that surrounding the casing will be generated with the casing, a second one of the tubes being connected at one end to an inlet in the casing, adapted to be connected to a fluid mixture of solids and liquids to be pumped and its opposite end being connected to a second outlet therein, whereby upon operation of the apparatus, the negative pressure will cause the second tube to move from a flattened state to a tubular state, whereby the fluid will be pumped though the second tube to the outlet, a settling tank, a pipe connecting the settling tank to the second outlet and means to introduce an elecical charge into the fluid mixture whereby solids will precipitate from the fluid in the settling tank.  
     
     
         3 . Apparatus according to    claim 1    or    2   , wherein the means for generating an electrical or electrostatic charge within the fluid comprises a plurality of strands of polypropylene or the like located within a tube through which the fluid is pumped.  
     
     
         4 . Appartus according to    claim 1   , wherein a receptor tank is provided for said fluid and said means for generating an electical charge comprises a pair of electrodes in the receptor tank for said fluid, said electrodes being connected to a source of low voltage AC current, and wherein said tank is earthed.  
     
     
         5 . Apparatus according to    claim 2   , wherein the means for generating an elctrostatic charge within said fluid comprises a plurality of strands of polypropylene secured within said sccond tube.  
     
     
         6 . Apparatus according to    claim 2   , whrein a receptor tank for said fluid and said means for generating an electical charge comprises a pair of electodes in the receptor tank for said fluid, said electrodes being connected to a source of low voltage AC current, and wherein said tank is earthed.  
     
     
         7 . Apparatus according to    claim 3   , wherein a receptor tank is provided for said fluid and said means for generating an electrical charge comprises a pair of electrodes in the receptor tank for said fluid, said electrodes being connected to a source of low voltage AC current. and wherein said tank is earthed.  
     
     
         8 . Apparatus according to    claim 1   , and including a tank through which at least part of said fluid is pumped, said tank incorporating an arcuate screen through which the fluid is forced by a plurality of brush heads having polypropylene bristles and supported on a rotor.  
     
     
         9 . Apparatus according to    claim 2   , and including a tank through which at least part of said fluid is pumped, said tank incorporating an arcuate screen through which the fluid is forced by a plurality of brush heads having polypropylene bistles and supported on a rotor.  
     
     
         10 . Apparatus according to    claim 3   , and including a tank through which at least part of said fluid is pumped, said tank incorporating an arcuate screen through which the fluid is forced by a plurality of brush heads having polypropylene bistles and supported on a rotor.  
     
     
         11 . Apparatus according to    claim 5   , and including a tank through which at least part of said fluid is pumped, said tank incorporating an arcuate screen through which the fluid is forced by a plurality of brush heads having polypropylene bistles and supported on a rotor.  
     
     
         12 . Appartus for separating solids from liquids in a mixture of solids and liquids, comprising a closed casing having a side wall, at least part of which is arcuate, and a pair of spaced opposed end walls, connected by said part arcurate side wall, a cage rotatable within the casing, the cage having rollers spaced around its periphery, and a first resilient tube extending around the cage and located between the peripheries of the rollers and the internal surface of the arcuate side wall, one end of the first tube being connected to a first outlet in a wall of the casing and the opposite ned of the tube being connected to means within the casing to hold open said end of the tube, there being a non-return valve associated with the first tube, means to cause rotation of the cage such that air within the casing will be drawn into the held-open end of the tube and pumped along the tube in peristaltic manner to the outlet, the non-return valve preventing air from re-entering the tube, whereby the pressure within the casing is reduced, relative to that around the casing, at least one further resiliently deformable tube entrained over at least some of the rollers of the cage, so as to extend between the rollers and the arcuate part of the side wall of the casing, one end of said further tube being connected to a second outlet in a wall of the casing and an opposite end thereof being connected to an inlet in a wall of the casing, said inlet being adapted to be connected to said mixture, whereby rotation of the cage not only reduces the pressure within the casing to cause the at least one further tube to expand into a tubular state, but also pushes said mixture to be pumped along the further tube from the inlet to the outlet, and means to generate an electrical or electrostatic charge within said mixture to separate liquids fro solids in said mixture.  
     
     
         13 . Apparatus according to    claim 12   , wherein a receptor tank is provided for said fluid and said means for generating a charge comprises a pair of electrodes in the receptor tank for said fluid, said electrodes being connected to a source of low voltage AC current, and wherein said tank is earthed.  
     
     
         14 . Apparatus according to    claim 12    or    13   , wherein said means for generating a charge comprises a plurality of strands of polypropylene secured within said second tube.  
     
     
         15 . Apparatus according to    claim 12    or    13   , and including a tank through which at least part of said fluid is pumped, said tank incorperating an arcuate screen which the fluid is forced by a plurality of brush heads having polypropylene bristles and supported on a rotor.  
     
     
         16 . Apparatus according to    claim 14   , and including a tank through which at least part of said fluid is pumped, said tank incorperating an arcuate screen which the fluid is forced by a plurality of brush heads having polypropylene bristles and supported on a rotor.  
     
     
         17 . Apparatus according to    claim 2    or    claim 12   , wherein the cage supports a plurality of guides for the respective tubes, said guides being provided on a plurality of shafts circumferentially spaced around the cage.  
     
     
         18 . Apparatus according to    claim 17   , wherein the shafts for guides are circumferentially spaced, around the cage, and separated by shafts carrying rollers.  
     
     
         19 . Apparatus according to    claim 2    or    claim 12   , wherein, on each guide shaft, three separate guides are provided, a central one being for the evacuating tube and located on either side thereof, there being a lateral guide for a respective pumping tube and wherein, on each roller shaft, thre is a central roller for the evacuating and spaced to either side thereof, a lateral roller for the respective pumping tubes.